"To me, this place is old Boston to its core. You can almost smell the cigar smoke," says Dennis Lehane, in scoop-necked black shirt and reddish stubble, a duplicate of his dust jacket photograph. He's talking about what is now the Park Plaza Hotel—its lobby an extravagant splendor of mirrors, marble, and gilded plaster lit by crystal chandeliers. Lehane set a key scene in his new novel, Live by Night (Morrow, Oct.), about Prohibition-era bootlegger Joe Coughlin, in this hotel, then called the Statler.

"Joe thinks he's an outlaw and ends up becoming a gangster," Lehane says. That is, Joe lives by a self-imposed moral code, which he eventually, inevitably, violates. "In the beginning, he's an iconoclast, not buying into institutional corruption. He doesn't want to be what his father represents, a corrupt cop. He sees massive hypocrisy in the way a loan shark is treated as compared to a banker. But what happens is what his father warns him about—the consequences of his violence. That becomes a central question of the book: can you retain your soul in this business?" Though operating in a criminal world, Coughlin doesn't see himself as a criminal. To him, an outlaw is a different animal. Coughlin originates in Lehane's previous historical, The Given Day (Morrow, 2008), about the 1919 Boston police strike and the flu pandemic after WWI. Lehane says that he fell in love with the character and was compelled to explore Coughlin's life further. "I'd done so much research for The Given Day that I felt steeped in the time. So when I started to work on this book, the writing was really flowing, the faucet was open… And, one of the reasons I write is because of all the Jimmy Cagney movies I watched when I was young. The gangster novel is my favorite sub-subgenre."

In Live by Night, Coughlin is drawn into a shootout that forces him to flee south and become a permanent snowbird. Lehane, 47, uses this novel to contrast the kind of love felt by a young man compared with that of an older man, and how it feels to have an obligation to the larger social structure. Through Coughlin, Lehane explores how time and family can change a man's priorities. Lehane himself divides his time between Massachusetts and Florida, where he teaches writing each spring at his alma mater, Eckerd College, in St. Petersburg. Much of Live by Night takes place in the Tampa neighborhood of Ybor City, "a mini New Orleans" of venerable houses with wrought iron grillwork, cigar factories, palm trees, and a population with Spanish, Cuban, and Italian roots. The locale, St. Petersburg and Tampa across the bay from each other, has lured Lehane for decades: "Tampa was the narcotics capital of America in the '20s, with a thriving trade in rum and illegal immigrants. But no writers were looking at Tampa—and it's such a romantic, sexy place. I'd loved Ybor since I went to college there in the eighties."

Lehane grew up in Boston's Dorchester neighborhood, the son of Irish immigrants who believed doggedly in the American dream. Today, the bestselling author retains a scrappy, populist worldview: "I have a lot of rage about things that didn't happen to me, tied up with watching an immigrant, working-class father struggle to make his way through the world—and seeing how society was modeled to keep him in his place." Early in his life, Lehane vowed to succeed as a novelist, and to shun the distracting niches he saw fellow novelists accept in teaching and advertising. He took " 'do you want fries with that' jobs" and lived like a college kid until he was 31. He remembers: "Until my fifth or sixth book was published, my father was calling me every time the post office had an exam."

Live by Night stands as one of Lehane's most enjoyable projects: "When I wrote this book, I knew every move to make without knowing how I knew. I think that's why the book is so much fun."

Stephen Anable is the author of two mysteries, The Fisher Boy (2008) and A Pinchbeck Bride (2011).